Automatically locking relay



R. P. DE ANTHONY ill-M37 AUTOMATICALLY LGKING RELAY May M9 948. v

Filed @CILI 5, 1945 4'@ @ma @a l N VE N TOR K r5 P0552 re/v THQ/Vy Patented May 1l, 1948 UNITED STATES PATENT OFFICE 2,441,137 AU'roMA'rroALLY LcxrNG RELAY Robert P. De Anthony, Dayton, Ohio Application october 5, 1943, serial No. 505,001

2 claims. (c1, zoo-c7) (Granted under the act of March 3, 1883, as

The invention described herein may be manufactured and used by or for Government for governmental purposes, without the payment to me of any royalty thereon. g

This invention relates to relay-s or circuit breakers, and the principal object is to provide a locking device which acts automatically to prevent the relay from closing the circuit after the latter has been opened, until an operator by manual or remote control has re-set certain mechanism. In general the invention provides means to prevent overloading of a power line by simultaneous closing of a number' ofrelays after a power outage. Other object-s will be understood from the following description of the preferred embodiment of `the invention shown in the accompanying drawings. wherein- Fig. 1 is an elevation of a relay equipped with the locking device, which is shown in unlocked position;

Fig. 2 is a fragmentary elevation showing the relay locked, with a remote control device added to permit releasing of the locking member from some distant point;

Fig. 3 is a fragmentary side elevation showing the locking member in cro-ss section and in armature-engaging position; and y Fig. 4 is a detail view in vertical section on an enlarged scale.

It is well known, in the art of automatic electric cut-outs or circuit-breakers, to provide an armature which is normally held in a certain position by an energized solenoid, the armature co-operating with a pair of contacts one of which is movable toV break the circuit when the armature is released by a power outage, together with a handle to restore the armature to the circuitclosing position. It has even been proposed, as in the Rogers Patent No. 677,843, dated July 2, 1901, to lock the armature handle by means of a manually moved catch. So far as I know, however. no one has employed an entirely automatic locking device as described and shown herein.

Referring particularly to the accompanying drawings, the improved circuit breaker or relay comprises a casing or box 5 which ordinarily will be closed by a cover not shown, said casing being adapted to be mounted on a panel or wall and having a number of apertures through which leads 6, 1 are inserted. Leads 6 are electrically amended April 30, 1928; 370 0. G. 757) connected with the terminals 8 of a relay solenoid 9, which is in series with the power circuit, so that whenever the source of electrical power energizes the leads 6, the solenoid will be maglnetlzed. Leads connect with a load circuit,

4which may include motors and other apparatus' not shown, and are electrically connected with` relay terminals I0, each terminal being secured to an insulator base II secured by screws I2 to a mounting block I3 which in turn is secured within the box 5. From one end of the solenoid a magnetizable core I4 projects, and an L-shaped armature I5, comprising a horizontal arm |5a and a vertical arm |5b, vis :io/supported thatit will contact the end of the core when attracted thereto by magnetism, or will move away from the core when the power fails and the solenoid is de-energized. To permit this movement of the armature. it is pivoted on the ends of a pin I8 which is secured to the upper face of the arm |5a. The pin ends are slidably and somewhat loosely received within'vertical slots I1 cut in the two downturned ends I8 of a bracket I9 xed to and extending transversely of the underside of a horlzontal arm 20 anchored at one end to base ll. To hold the armature yieldably below arm 20, a coil spring 2| is carried on a pin 22 riveted or weldediat its upper end to arm 20 and passing through an aperture 22a in arm |511 of the armature. At its lower end, pin 22 is screw-threaded as at 23 and a knurled nut 24 engages the screw threads and permits manual adjustment of the compression of the coil spring, whose upper end presses against arm lia. Nut 2l may be a lock nut (not shown). Thus the armature may pivot on pin I6 and may move up and down in slots I1, any downward movement, however, being opposed by the compressed spring 2|, which therefore normally holds the armature pivot pin in the upper ends of the slots.

To complete the circuit between terminals I0, a contact plate 25 of conducting material is supported on the armature to move therewith and has contacts 26 at each end, on the underside, for

direct engagement with xed contacts 21 secured to terminals I0. If desired an insulating plate (not shown) may be attached to the upper face of contact plate 25 to obviate possible short circuits. To assist in holding the armature in the position of Fig. 3, a coil spring 28 is carried by a fixed pin 29 whose lower end is screw-threaded as at 30 to receive a spring-tension-adjusting nut 3| (which may be a lock nut) and whose upper end is fixed to arm 20. A washer 32 is slidably carried by the pin 29 and is pressed against the underside of armature arm I5a by coil spring 28. Washer 32 may be integral with or secured to a sleeve 33 which is slidable on pin 29 and nts within the coils of spring 28 to pre- `vent lateral movement of said spring. Another sleeve 34 is slidable on pin 29 and is received in the forked end lic o! arm Iba, with its lower end in contact with washer 32. Contact plate 25 has an aperture through which sleeve 34 projects. A washer 35 is placed above the contact plate and another washer 36 is below said plate, both washers -surrounding sleeve 34. When the armature is de-energized, arm 15a rises, and sleeve 34 then moves against plate 29, which acts as a stop. No novelty is claimed for the parts so far described.

Pivoted on a bracket 31 in turn secured to casing is a locking member or lever 3B adapted to `swing vertically, and having an enlarged end 38a adapted to rest on the top edge of the armature arm |517 (Fig. 1) or move down into the space between the armature and the core I4 (Fig. 3) to lock the armature against movement toward the core. As the locking member bridges said y space, it is formed from insulating material.

While the enlarged lever end 38a may be weighted, to cause the latch automatically to fall into said space, I prefer to effect positive action of the locking lever 38'by employing a coil spring 39 carried on a vertical rod 40, the lower end of spring 39 engaging a part of the casing, the upper end engaging spring follower 4I slidable on block i3 and adjustably secured to rod 49 by means of screw 4|a. An abutment 42, also adjustable on rod 40, engages the end 38h of lever 38 to move said end upwardly by expansion of spring 39, when the position of the lever permits this action. But as long as the lever end 38a rests on top of the armature, spring 39 is ineiective. A light spring 43 presses with its lower end against a spring follower 44 slidable on rod 40 and engageable with the upper side of lever end 38h, thus insuring engagement of said lever end with abutment 42. The upper end of spring 43 abutsan adjustable stop 45 on the rod, so that the compression of the light spring isalso variable. A L its lower end, rod 40 extends through and outside of the casing and carries a knob or handle 46 by which the rod may be pulled downwardly to raise the locking lever to the armature-freeing position of Fig. 1. To signal the .position of the locking lever, which normally is concealed behind the cover to the box 5, an annunciator or signal 41 may be secured on top of the casing and may be operated by a rod 48 joined by a pair of tie bars 49 to the upper end of rod 40, thus indicating the on or off positions of the relay.

In the modification of Fig. 2, the construction and action are the same except that instead of manual resetting being used alone to restore the locking lever to its inactive position, a solenoid 50 is secured inside box 5 and has its armature 5| directly connected with an arm 52 secured to adjustable spring follower 54, which corresponds to follower 4l, Fig. 1, Solenoid 50 is coupled by leads 55 to a circuit which may control the solenoid from any remote point, so that the operator may restore the relay to its normal condition Without going to the relay and manipulating the knob.

Both forms of the invention are effective in locking the relay armature and thus preventing restoration of the load on the line until the operator has sequentially coupled the motors and other electrical apparatus into the circuit and unlocked the relay. This my invention may prevent burning up motors. also blowing ot fuses or opening or circuit breakers due to excessive initial load on a power line.

Obviously the present invention may be embodied in several forms neither described nor shown, and may be useful with switches, relays or circuit-breakers of various constructions.

What I claim is:

1. In a circuit breaker or relay having a solenoid and a swingably mounted armature including an upwardly extending arm which is moved by energization and de-energization of the solenoid, and contact means moved by action of the armature to make and break a circuit; the improvement which comprises a locking member mounted on the relay to be swingable in a substantially vertical plane and having an extending part which rests inactive on the upper end of the armature arm while that is in engilement with the energized solenoid, whereby said part automatically drops between said arm and sclenoid into locking position when the armature swings into release position upon de-energization of the solenoid for preventing closing of the circuit until actuated by an operator, and operator controlled means to restore the locking member into its inactive position, 4

2. In a circuit breaker or relay having a solenoid and a swingably mounted armature includlng van upwardly extending arm which is moved into solenoid engaging position and into release position, respectively, upon energization and deenergization of the solenoid, and contact means moved by action of the armature to make and break a circuit; the improvement which comprises a locking lever pivotally mounted on the relayto be swingable in a substantially vertical plane and having a weighted end part resting inactive on the upper end of the armature arm while that is in engagement with the energized solenoid and whereby said part automatically drops between the solenoid and armature arm into locking position when the armature swings into release position upon de-energization of the solenoid, for positively retaining the circuit open until actuated by an operator, operator controlled means to restore the locking lever into its inactive position, and adjustably mounted spring means to aid said weighted means for causing quick movement oi the lever into locking position.

ROBERT P. DE ANTHONY.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS Number Name Date 645,958 Keller Mar. 27, 1900 786,017 Dutton Mar. 28, 1905 863,238 Thullen Aug. 13, 1907 1,182,234 Wheeler May 9, 1916 1,251,294 Scott Dec. 25, 1917 1,323,741 Buechler Dec. 2, 1919 1,789,730 Demasters Jan. 20, 1931 1,838,818 Fitzpatrick Dec. 29, 1931 2,284,621 Kuhn et al June 2, 1942 

